Apparatus for vibrating seats

ABSTRACT

A driver&#39;s seat having a vibration generator connected to the driver&#39;s seat and controls for turning the vibration generator on and off for vibrating the driver&#39;s seat so that when a driver feels drowsiness coming on, the driver can operate the controls for switching on-off the vibration generator so that the driver&#39;s seat can be vibrated and prevent the driver from dozing during driving and prevent an accident from occurring.

FIELD OF THE INVENTION

The invention relates to an apparatus used for vibrating a driver's seatof automobiles, and the like to keep a driver alert and prevent a driverfrom dozing during driving.

BACKGROUND OF THE INVENTION

A variety of apparatus have been proposed to keep a driver alert andprevent a driver of automobiles and the like, from dozing duringdriving. Such apparatus usually comprise a sensor for sensing that adriver has started to doze and means for wakening a driver by receivinga signal from the sensor. For example, there is a sensor which sensesthat a driver has started to doze by sensing the number of times thedriver nods per unit time or the time for leaning one's head forward,and the like, because a driver nods when the driver starts to doze, andsends a signal to means for alerting the driver. Also, there are meansfor alerting a driver which operates by receiving the signal, andalerting the driver by producing a loud sound in the driver's ear orears. Therefore, according to this apparatus, if a driver starts todoze, the sensor senses that the driver's head is leaning forward, andactuates the means for alerting or wakening the driver.

OBJECT OF THE INVENTION

However, because the above mentioned apparatus operates only after adriver has started to doze off, the driver may lose concentration, dueto drowsiness, when the driver has started to doze, to such a degreethat the means for alerting and wakening the driver may not beeffective.

Accordingly, the objection of this invention is to provide apparatus forpreventing a driver from dozing off by vibrating the seat.

DISCLOSURE OF THE INVENTION

In order to accomplish the above objection, the apparatus of thisinvention for vibrating seats comprises a driver's seat and means forvibrating such driver's seat and means for controlling the on-off ofsuch means for vibrating the driver's seat.

As a result of a series of studies of apparatus to effectively preventdozing during driving, the inventors have discovered that it is too lateto prevent accidents when a driver is taken through a sensor that sensesa driver has started to doze. The inventor has discovered that, if adriver's seat is always being vibrated, the driver remains alert, cannotdoze off and, as a result, traffic accidents caused by dozing duringdriving can be completely prevented.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be more fully described and will be better understoodfrom the following description, taken with the appended drawings, inwhich:

FIG. 1 is a side view of one embodiment of the present invention;

FIG. 2 is a top plan view of the apparatus of FIG. 1 with the driver'sseat removed;

FIG. 3 is a side schematic view of an automobile incorporating theinvention of FIG. 1;

FIG. 4 a vertical sectional view of the vibrator of the one embodiment;

FIG. 5 is an enlarged view, partly in section, of the apparatus of FIG.1;

FIG. 6 is a top view of the driver's seat and the control panel forcontrol of the apparatus of FIG. 1;

FIG. 7 is a rear view of the apparatus of FIG. 6;

FIG. 8 is a side view, similar to FIG. 1, but showing another embodimentof the invention;

FIG. 9 is a front view, partly in section, of the vibrator arrangementof the embodiment of FIG. 8;

FIG. 10 a side view, similar to FIG. 8, but showing a still furtherembodiment of the invention;

FIG. 11 is a front view, partly in section of the embodiment of FIG. 10;

FIG. 12 is a side view, similar to FIG. 10, showing yet anotherembodiment;

FIG. 13 is a rear view of the embodiment in FIG. 12;

FIG. 14 side view, partly in section, of still yet another embodiment;

FIG. 15 is a rear view of the embodiment of FIG. 14;

FIG. 16 is a side view, partly in section, of still a furtherembodiment, of the invention;

FIG. 17 is a side view, partly in section, of the embodiment of FIG. 16,with the apparatus in a different position;

FIG. 18 is a side view, partly in section, of a further stillembodiment, similar to FIG. 16;

FIG. 19 is a side view of the apparatus of FIG. 18 with such apparatusin a different position;

FIG. 20 is a side view, partly in section, of still another embodimentof the invention;

FIG. 21 is a side view, similar to FIG. 20, but with the apparatus in adifferent position; and

FIG. 22 is a side diagrammatic view, of a still further embodiment ofthe apparatus of the invention.

The following are detailed descriptions of the various embodiments.

FIG. 1 shows a side view of the first embodiment of the invention, has astructure for vibrating a driver's seat 1 by a motor 10 installed on theunderside of the driver's seat wherein the vibration is transmitted tothe driver's seat 1 when vibration motor 10 is activated. Driver's seat1 is mounted on base 2 and, as best shown in FIG. 2, is attached to base2 by angle fasteners 3 shaped like an L, and which face each other, at aposition toward the front and a rear end of base 2. Stationary platesla, are fixed, by bolts 4, on the radial outward slants cf said anglefasteners 3 at the front end and the rear end of the base of seat 1. Theother side of angle fasteners 3 are welded on the upper side of base 2.Vibration motor 10 is fixed with bolts 5 on the underside of base 2.Output shaft 10a of vibration motor 10, extends horizontal in right andleft direction, as viewed from the front of the driver's seat 1 and fromthe front of automobile 15 shown in FIG. 3. As shown in FIG. 4,eccentric loads 13, comprising fixed load 13a and an adjustable load13b, are installed on opposite ends 10b of output shaft 10a, thedirection of rotation being indicated by an arrow in FIG. 1 of vibrationmotor 10. The centrifugal force caused by eccentric loads 13, rotatingat the opposite ends of output shaft 10a, causes base 2, and seat 1mounted thereon, to vibrate. In FIG. 4, 10c is a stator core and 10d isa rotor core of vibration motor 10 which is an electric motor.

Base 2, supporting seat 1 is elastically supported by its corner, FIG.2, on bed 6. Bed 6 is fixed on the floor 16 of an automobile 15, FIG. 3.Hollow rectangular barrel frames 7, FIGS. 1 and 2, comprising of framebodies 7a and 7b, FIG. 5, are welded together on the front and rear onthe upperside of bed 6, and spring supports 8 are installed on the rightand left, FIG. 1 and 5, front and rear, FIG. 2, of the upperside ofrectangular barrel frames 7. Spring supports 8 each comprise a disc typebottom part 8a, support parts 8b installed on the middle of theupperside of disc type bottom parts 8a, and passages 8c penetrating bothbottom parts 8a and support parts 8b. Bottom parts 8a are fixed on theupperside of rectangular barrels 7 with screws 9. Support parts 8b areengaged, from the outside, with springs 11. Bolts 12 are insertedthrough each passage 8c. Each bolt 12 is inserted from the uppersideinto each bolt hole 2a, on base seat 2. The nut screw part of each bolt12 is fixed such as by welding on the ceiling of each rectangular barrel7. Thus, the underside of the base 2 for installation of seat 1 iselastically suspended on the upper end of springs 11.

In an automobile 15, FIG. 3, as shown in FIGS. 6 and 7, a controllerconsole panel 14 is set up on the right side, facing forward, of thedriver's seat 1. On console panel 14, power-on switch 14a, power-offswitch 14b, operation switch 14c, frequency handle 14d, enabling thespeed and the number of vibration frequency of vibration motor 10 to bevaried and set at a desired frequency, and a timer 14e, for settingtimer for start-up and stopping of vibration motor 10 and seat vibrationcaused thereby, are arranged. Controller console panel 14 also containsan inverter (not shown) so that an electric current from a battery 17installed in the front part of an automobile 15 is converted intoalternating current for supply to the vibration motor 10. In this firstembodiment, the apparatus can provide the driver's seat, whose maximumunload is 100 kgs., with 20 Hz in the number of vibration frequency and15 mm of the amplitude of the vibration for vibrating the driver's seat1 up-down and back-forth.

When the driver feels drowsiness coming on the driver can turn onpower-on-switch 14a and then turn on operation-switch 14c so thatvibration motor 10 operates, generates vibration and such vibration istransmitted through base 2 to driver's seat 1 through support boards 3and stationary plate 1a to driver's seat 1 and driver's seat 1 vibrateson springs 11. The vibrating driver seat 1 keep the driver alert andwards off dozing during driving.

In FIGS. 8 and 9, a modification of the embodiment of FIGS. 1-7 is shownand will now be described. In this second embodiment, a pulley base 22is set up on the underside of the base 2. Vibration motor 10 is fixed bybolts 23 on the underside of the pulley base 22. Rubber vibrationinsulators 24, covering bolts 23 are fixed between the upperside ofsupport 10b of vibration motor 10 and the underside of pulley base 22.Power transmission shaft 25, on which pulley 26 is mounted, is installedhorizontally between left wall 22a and right wall 22b of pulley base 22,under driver's seat 1 and is connected by belt 21 to pulley 20 mountedon output shaft 10a of vibration motor 10. Support parts 27, FIG. 8, areset up on the bed 6, whereby the driver's seat is elastically suspendedthrough rubber vibration insulators 28. Parts, except for thosedescribed above, are the same as those in the first embodiment and thesame numbering is adopted. In FIG. 9, 29 and 30 are bearings.

According to this second embodiment, vibration generated by vibrationmotor 10 is transmitted mainly through lower pulley 20 and belt 21 tothe upper pulley 26, furthermore, from upper pulley 26 through powertransmission shaft 25 to the base 2 for the driver's seat 1, and so on.

Rubber vibration insulators 24 on the pulley base 22, receivingvibration motor 10, reduce troubles caused by vibration.

FIGS. 10 and 11 show a third embodiment of the invention similar to thefirst and second embodiments. In such third embodiment, a motor 32 isinstalled on the underside of receiving the pulley base 22 and aneccentric load 34 is fixed on power transmission shaft 33 supported forrotation on walls 22a (left) and 22b (right) of pulley base 22. Theother parts in the embodiment are the same as those of the secondembodiment and the same numbering is adopted.

According to this third embodiment, when the rotation of the motor 32ais transmitted through output shaft 32a of motor 32, pulley 20 and belt21 to pulley 26 and power transmission shaft 33, eccentric load 34 onpower transmission shaft 33 vibrates and such vibration is transmittedto base 2 of driver's seat 1. In this third embodiment, motor 32,itself, does not vibrate and the durability of the motor 32 isdrastically improved.

In the above first through third embodiments, the power transmissionshafts of the vibration motor and pulley shafts extend transverse thedirection of travel of the vehicle 15, FIG. 3. However, this is notintended as limiting in scope and also each of them can be installed inthe same direction as the direction of travel of the vehicle 15.

Also, in the above first through third embodiments, a bed 6 is fixed onthe floor 16 of vehicle 15. This, also is intended not as limiting inscope and the base 6 may be fixed on the floor 16 slidably in back-forthdirections.

FIGS. 12 and 13 show a fourth embodiment of the invention. In suchfourth embodiment, a U-shaped flat spring 42 is installed between adriver's seat 1 and a base 38 and an electro-magnet 43 is connected toone of the ends 42a and 42b of the flat spring 42, while a permanentmagnet 44 is connected to the other of the end 42a and 42b. Vibration ofspring 42 is generated by sending electrical current into electro-magnet43 and such vibration is transmitted to the driver's seat 1 so that thedriver's seat 1 vibrates. In detail, an upper vibrating body 40 is fixedunder the driver's seat 1 and a concave part 40a is formed in the middleon the underside of said vibrating body 40. And also, the lowervibrating body 41 is fixed on the upperside of said base 38 by bolts 47and a rubber vibration insulator 48, which covers bolts 47, is fixedbetween the upperside of the base 38 and the underside of lowervibrating body 41. A concave part 41a is formed in the middle on theupperside of vibrating body 41. A U-shaped flat spring 42 is mountedbetween concave parts 40a and 41a. Height-adjustable bolt 39, isadjustable to fix the height of base 38 on the floor 16 of automobile15, FIG. 3.

The underside of lower bar 42a of flat spring 42 is welded to the bottomface of concave part 41a of lower vibrating body 41, while the uppersideof upper bar 42b of flat spring 42 is welded on the upperside of concavepart 40a of upper vibrating body 40. An electro-magnet 43 having a fixediron core 46 wound with coil 45, is fixed on the upperside of lower bar42a of flat spring 42, while a moving iron core 44 is fixed on theunderside of the upper bar 42b. Support board 48 is fixed on the sidepart of lower vibrating part 41 by a bolt 49. Controller 50 is fixed onsupport board 48 by a bolt 51. Controller 50 contains an inverter, sameas in the above Example 1, and also electric current adjustable handle51a, and the like, and controlling alternating current supplied to coil45, are installed on console panel set up in the rear side of controller50.

As shown in FIG. 13, lower vibrating body 41 and upper vibrating body 40are connected, at opposite right and left sides, by flat spring 52.Thus, the upper part of flat spring 52 is fixed on the upper stay 55,fixed on said upper vibrating body 40 by bolts 54, while the lower partof flat spring 52 is fixed on the lower stay 58, fixed on the lowervibrating body 41 by bolts 57. In such a fixed state, flat spring 52 istilted toward the rear, as shown in a chain line of FIG. 12, so that itworks to set resonance frequency. In the third embodiment, 100 kgs. fora seat maximum load, 20 Hz for number of vibration frequency and 15 mmvibration for amplitude (vertical vibration of the driver's seat 1 suchthat its vibration is a little tilted backward direction) are given tothe driver's seat 1.

In the fourth embodiment, if a driver feels drowsiness coming on, thedriver can turn on power-on switch and then operate an electric currentadjustable handle 51a, installed on a console panel, so that suitablealternating current is sent to a coil 45 of electro-magnet 43. Becausemagnetic flux is generated on fixed iron core 46 of the electro-magnet43, moving iron core 44 is attracted toward fixed iron core 46 and therear part of upper vibration body 40 is tilted downward. When thealternating current becomes zero, the attracting force becomes zero andat the moving iron core 44 is returned to the original position byelastic stress of flat spring 42. In addition, both flat springs 42installed between opposite sides of lower vibrating body 41 (left) andsaid upper vibrating body 40 (right) establish resonance frequencytrailing the movement of upper vibration body 40. Thus, lower vibratingbody 41 and upper vibrating body 40 vibrate vertically (in a directiontilted backward a little), and such vibration is transmitted, throughupper vibrating body 40, to the driver's seat 1. A driver seated in thedriver's seat 1 is kept alert by the vibration of the driver's seat andis not liable to doze off during driving.

FIG. 14 and 15 show a fifth embodiment. In the fifth embodiment, agroove 41b is formed on the bottom face of the concave part 41a of lowervibration body 41 and the lower end of compression coil spring 60 ispositioned in groove 41b and fixed. Groove 40b is formed on theupperside of the concave part 40a of upper vibration body 40, and theupper end of said compression coil spring 60 is positioned in groove 40band fixed. Electro-magnet 43 is fixed on the bottom face of concave part41a of lower vibration body 41 inside of compression coil spring 60.Moving iron core 44 is fixed on the upperside of the concave part 40a ofthe upper vibration body 40 inside the compression coil spring 60. Asshown in FIG. 15, lower vibration body 41 and upper vibration body 40are connected with flat spring 61 at its opposite right and left ends ofbody 41. One end of flat spring 61 is fixed by a bolt 62 on a lower stay64 fixed on lower vibration body 41 by a bolt 63, while the other end isfixed by a bolt 65 on the upper stay 67, fixed on upper vibration body40 by bolt 66. Flat spring 61, in such a fixed state and in a horizontalposition, as shown by a chain line of FIG. 14, operates so as to setresonance frequency. In this fifth embodiment, mainly, a verticalvibration is given to the driver's seat. The other parts, except for theabove, are the same as those of the fourth embodiment and the samenumbering is adopted.

In the above fourth and fifth embodiments, electro-maqnet 43 is used forthe lower vibration body 41 and a moving iron core 44 is used for theupper vibration body 40. This, however, is intended not as limiting inscope and it is possible that electro-magnet 43 is used for the uppervibration body 40 and a moving iron core 44 can be used for the lowervibration body 41.

In the sixth embodiment of FIG. 16, a pneumatic cylinder vibratesdriver's seat 1. A pneumatic cylinder 70, having an upper wall 71a, hasa rod 72 passing through in rod hole 71b, formed on the middle part ofan upperside 71a of cylinder body 71. The driver's seat 1 is fixed onthe upper end of rod 72, while piston 73 is fixed on the lower end.Piston 73 is slidable, vertically, in cylinder chamber 74, the pistondividing cylinder chamber 74 into an upper chamber 75 and a lowerchamber 76. A spring 77 is arranged between the concave part of theupper side 71a of cylinder body 71 and the concave part of the uppersideof the piston 73, and piston 73 is pressed downward by energy of spring77. A line 78 is extended from lower chamber 76 and connected to achannel control valve 80.

In channel control valve 80, a valve rod 82 is arranged slidably insidea casing 81 and an iron core, or permanent magnet 83, is installed atthe left end of the valve rod 82. A maximum diameter part 82a is formedin valve rod 82, dividing the casing 81 into two parts, a right chamber84 and a left chamber 85. Electromagnet 86 is fixed on a part of thehousing of control valve 80 to the right from the left end by a definitedistance on the chamber 85, while air-supply line 88, extended from acompressor 87, is connected to chamber 85. Spring 89 is positioned inright chamber 84 and valve rod 82 is pressed toward the left, FIG. 16,by energy of the spring 89. A passage 90 to atmosphere, leads from rightchamber 84 to the atmosphere outside.

Electro-magnet 86 is electrically connected, through an inverter, with abattery 17 of an automobile 15 such as in the fourth embodiment. And anon-off switch for vibration, which controls the supply of electricity toelectro-magnet 86, is arranged on a console panel 18 of an automobile15, FIG. 3. When the switch for vibration is pushed, the electro-magnet86 is charged with alternating current.

In this embodiment, as shown in FIG. 16, in normal condition thevibration switch is not pushed and electro-magnet 86 is not charged withelectricity and magnetic force is not generated in the electro-magnet86. The valve rod 82 is pushed to the left by elastic energy of spring89 and contacts the leftside of a casing 81, wherein the maximumdiameter part 82a of valve rod 82 is positioned between the connectedline 78 and air supply line 88. Thereby, connected line 78 and passageto the atmosphere 90 are connected through the right chamber 84, whilethe communication of a line 78 and air supply line 88 are cut off by themaximum diameter part 82a. Therefore, the air of lower chamber 76 isconnected to the atmosphere so that piston 73 is pressed downward todownside of the cylinder 71 by elastic energy of the spring 89 and thedriver's seat 1 is supported by the upper wall 71a of cylinder body 71.In this case, the air from a compressor body 87 is released to theatmosphere outside by the compressor body 87, itself, or means forreleasing air, which is arranged in the air supply line 88 (not shown inFigures).

When a driver feels drowsiness coming on during driving and the driverpushes on a switch for vibration, electro-magnet 86 is not charged withalternating electricity. At that time, magnetic force is generated insaid electro-magnet 86 intermittently in a short pitch, wherein ironcore 83 is attracted toward the position where electro-magnet 86 isinstalled, that is toward the right, FIG. 16. Therefore, the valve rod82 moves against elastic force of the spring 89, and, as shown in FIG.17, the communication of the line 78 and the passage to atmosphere 90 iscut off by maximum diameter part 82a and line 78 and the passage to airsupply line 88 are connected through chamber 85. Air, at air pressure of3-5 kgs) is force-feeded from compressor 87 into a lower chamber 76.Piston 73 (the area receiving the pressure is 20 cm²) rises and thedriver's seat 1 rises together. In the condition that magnetic force isnot generated in electro-magnet 86, as mentioned in the above, becauseline 78 and the passage to atmosphere 90 are connected, the air in thelower chamber 76 is connected with the outside atmosphere, FIG. 16, thepiston 73 is pressed downward by the energy of the spring 77 and alsothe driver's seat lowers. The raising and lowering of the driver's seat1, like this repeats while the switch for vibration is pressed. In thisway, if a driver feels drowsiness, the driver can vibrate the driver'sseat 1 by repeating rise and fall of such driver's seat by operating theswitch for vibration installed in the control panel 18. Therefore, thedriver remains alert, does not doze off during driving, and trafficaccidents caused by dozing during driving can be prevented.

In the seventh embodiment of the invention shown in FIG. 18, means forreleasing air from compressor 87 into the atmosphere outside isinstalled in the channel control valve 91. This means that in thechannel control valve 91 of this embodiment, as shown in FIG. 18, themaximum diameter parts of 92a and 92b of valve rod 92, are formed at thedefinite distance between them in the valve rod 92, whereby the casing93 is divided, respectively, into a right chamber 95, a middle chamber96 and a left chamber 97. Also, a line for releasing force feed air 94is arranged in the casing 93, whose end opens to the outside of theautomobile through a hole (not shown in Figures) formed in the floor 16of the automobile 15, FIG. 3, into the atmosphere outside. The otherparts, except for these parts, are the same as those of the aboveExample 6 and the same numbering is adopted.

According to the seventh embodiment, the connected line 78 and the airsupply line 88 are connected through the middle chamber 96 when magneticforce is generated in electro-magnet 86, as shown in FIG. 18. Theconnected line 78 and the line for the passage to the atmosphere 90 areconnected through the right chamber 95, while the air supply line 88 andthe line for releasing force feed air 94 are connected through themiddle chamber 96, when magnetic force is not generated inelectro-magnet 86, as shown in FIG. 19. Thereby, when the compressor 87is driving, the air pressed by compressor 87 is not sent to the lowerchamber 76 of the cylinder chamber 74 so that the air can be dischargedto outside of the automobile.

In the embodiments, the combination of the valve rod 82 (92) combinedwith the spring 89 are adopted for the channel control valve 80 and 91.However, a rotary valve type is also acceptable.

In the eighth embodiment of FIG. 20, the driver's seat 1 is vibrated bya hydraulic cylinder. In detail, in hydraulic cylinder 120, a T-shapedpiston rod 123 slides vertically. The driver's seat is fixed on asupporting part of the seat 123a formed at the upper end of piston rod123. The cylinder chamber has a pressure chamber 126 formed betweenupper and lower hydraulic packings 122a and 122b, respectively.Pressured chamber 126 is divided into an upper pressure chamber 124 anda lower pressure chamber 125 by a maximum diameter part 123b formed onpiston rod 123.

In servo valve 101, pilot stage 102 and power stage 103 are formed, andfirst valve rod 104 is arranged vertical-sliding-freely in the pilotstage 102, while the second valve rod 105 is arrangedvertical-sliding-freely in the power stage 103. Pilot stage 102 isconnected through fifth line 106 to an upper part of power stage 103,and through sixth line 107 to a lower part of power stage 103. Powerstage 102 is connected through the first line 127 to an upper pressurechamber 124 of the cylinder chamber and through the second line 128 to alower pressure chamber 125, through third line 113 to a hydraulic pump,not shown, and through forth line 115 to first line for returning oil114, respectively. A vibration generator, by dynamic electricity 108, isarranged under pilot stage 102. Coil 108a is positioned inside itsvibration generator by dynamic electricity 108 while controlled body 110is energized, upward, by a spring 109 in the upper part of the vibrationgenerator 108. Coil 108a is, as in the fourth embodiment, electricallyconnected through an inverter with the battery 17 of the automobile 15,FIG. 3. Electricity supplied from the inverter to the coil 108a isconverted into alternating current. An on-off switch, not shown,controls electric supply to coil 108a and is installed in the controlpanel 18, so that the controlled body 110 can be controlledvertical-sliding-freely by sending alternating current to coil 108a.Since controlled body 110 contacts first valve rod 104, the first valverod 104 is energized upward. And also first valve rod 104 is energizedupward by an extension spring 111 fixed on the upper part of the pilotstage 102. The first displacement transducer 112, which detects adisplacement in the lower part 105a of the second valve rod 105, isinstalled in the lower part of the power stage 103. The detection signalis sent to the vibration generator by dynamic electricity 108 asfeedback. On the other hand, the second displacement transducer 129,which detects displacement in the lower part 123b of piston rod 123, isinstalled in the lower part of cylinder chamber 126. Such detectionsignal is sent to the vibration generator by dynamic electricity 108 asfeedback. In FIG. 20, 116 is the second line for returning oil 117 isthe seventh line connected with the hydraulic pump and 118 is adiaphragm, which are installed in the oil tight condition, on thecontrolled body 110 and the vibration generator by dynamic electricity108.

In the above structure, when alternating current is sent to the coil108a of the vibration generator by dynamic electricity 108 so that thecontrolled body is moved upward, as shown in FIG. 21, the first valverod 104 moves upward and the seventh line 117 is connected with thesixth line 107 so that oil force fed by the hydraulic pump is suppliedfrom the lower end of the power stage 103 to inside the power stage 103.At that time, the second line for returning oil 116 and the fifth line106 are connected so that oil is returned from the upper end of thepower stage 103 to a tank (not shown in Figures). Thereby, the secondvalve rod 105 moves upward and, as a result, the third line 113 isconnected with the second line 128 so that the oil from the hydraulicpump is supplied to the lower pressure chamber 125. The first line forreturning oil 114 and the first line 127 are connected through thefourth line 115 so that oil is returned from the pressure chamber 124 tothe tank. Thereby, piston rod 123 is moved upward and the driver's seat1 rises. When the controlled body 110 is moved downward, in an oppositereaction against the above, the piston rod 123 is moved downward so thatthe driver's seat falls. Thus, accompanying with the vertical movementof the controlled body 110, the driver's seat 1 vibrates. In this case,the amount of inflow oil and outflow oil to a lower pressure chamber 125or an upper pressure chamber 124, changes by the displacement of thefirst valve rod 104 in the pilot stage 102, so that the piston rod 123vibrates at a speed in proportion to the oil flow. The detection signalsfrom the first displacement transducer 112 and the second displacementtransducer 129 are sent to the vibration generator by dynamicelectricity 108 as feedback, which enables precise control.

In the eighth embodiment, if a driver feels drowsiness coming on, thedriver can operate switches installed on a control panel such as controlpanel 14, FIG. 6, whereby alternating current is sent into the coil 108aof vibration generator by dynamic electricity 108 so that a servo valve101 operates to supply oil from the hydraulic pump to the pressurechambers 124 and 125 of the hydraulic cylinder 120 and the piston rod123 moves vertically and the driver is kept alert and traffic accidentswill be prevented.

In the ninth embodiment in FIG. 22, the vibration generator, by dynamicelectricity 130, is adapted to vibrate the driver's seat 1. In detail,support axes 133 of the vibration generator, by dynamic electricity 130,are extended from opposite sides, at the right and left in horizontaldirection, and supported by support base, not shown. And also, in thevibration generator by dynamic electricity 130, a base 135, wherein thedriver's seat is fixed, is supported by iron core 134. The iron core 134has an annular body magnetic pole 136, an annular upper yoke 137 fixedon an upper part of annular body magnetic pole 136, an annular loweryoke 138 fixed on a lower part of body magnetic pole 136, an annularupper center magnetic pole 139 and a lower center magnetic pole 140,arranged concentrically, wherein annular exciting coils 143 and 144 arearranged concentrically in two divided spaces of upper annular chamber141 and lower annular chamber 142 formed thereby. Both exciting coils143 and 144 are, like in embodiment four, electrically connected withthe battery 17 of the automobile 15, so that the battery supplies directcurrent to both exciting coils 143 and 144.

An annular cavity 145, connecting the spaces of upper chamber 141 andlower chamber 142, is formed concentrically with exciting coils 143 and144 in a central annular projecting portion 136a of body magnetic pole136, while a bore 146 is formed through the center of upper centermagnetic pole 139. Linear ball bearing 149 is fixed on the upper part ofpit 146. A connecting holes 151, connecting with upper space 141, areformed at regular intervals in upper yoke 137. A hole of small diameteris formed on the upper portion of lower center magnetic pole 140, and ahole of larger diameter is formed under the hole of small diameter.Linear ball bearing 147 is fixed in the small diameter while air spring148 is positioned in the hole of larger diameter.

Supporting rod 150, which extends downward from the center of theunderside of base 135, passes through bore 146 of upper center magneticpole 139 and the hole of small diameter of lower center magnetic pole140 and is supported by air spring 148, for freevertical-sliding-movement by linear ball bearings 147 and 149.Connecting piece 152 extends downward through connecting hole 151 on thelower part of base 135, and is connected, through connecting hole 151,with annular driving coil 153. Driving coil 153 is arranged in thecavity concentrically with concentric exciting coils 143 and 144.Driving coil 153 is electrically connected, through an inverter, withbattery 17, whereby electricity, supplied to the driving coil 153 isconverted into alternating current. An on-off switch, not shown,controls the supply of electricity to driving coil 153 and is arrangedin a control panel, such as control panel 14, FIG. 6. In FIG. 22, 154 isan air seal and 155 is a loop spring, which works as a baffle.

In the ninth embodiment, when the switch of the control panel is turnedon, direct current is charged through exciting coils 143 and 144 andmagnetic flux in the direct of arrow A is formed and alternating currentis charged through the driving coil 153 at right angles to the magneticflux of the direct current in coils 143, 144. According to Fleming'srule, an excitation force works in the B arrow directions, and thedriver's seat vibrates. Therefore, if a driver feels drowsiness comingon, the driver can vibrate the driver's seat 1 by turning on the switch,preventing dozing during driving and accidents caused thereby.

EFFECTS OF THE INVENTION

Thus, according to this invention, a driver's seat having a vibrationgenerator connected to the driver's seat and controls for turning thevibration generator on and off for vibrating the driver's seat so thatwhen a driver feels drowsiness coming on, the driver can operate thecontrols for switching on-off the vibration generator so that driver'sseat can be vibrated and prevent the driver from dozing during drivingand prevent an accident from occurring.

What is claimed is:
 1. An apparatus for vibrating a seat, comprising:adriver's seat; base means for supporting said driver's seat; fastenermeans for supporting said seat onto said base means, said fastener meansbeing positioned between said seat and said base means; vibrating meansfor vibrating said driver's seat, said vibrating means being mountedunderneath said base means; spring means for resiliently supporting saidbase means onto a bed member; and control means for controlling saidvibrating means in vibrating the seat,
 2. An apparatus for vibrating aseat as recited in claim 1, wherein said fastener means comprises aplurality of angle fasteners, each having a substantially L-shapedconfiguration, and having at least a stationary plate bolted onto aradial outward slant thereof.
 3. An apparatus for vibrating a seat asrecited in claim 1, wherein said vibrating means for vibrating saiddriver's seat comprises a vibrating motor connected to said driver'sseat.
 4. An apparatus for vibrating a seat as recited in claim 3,wherein said vibrating motor includes an output shaft having, onopposite ends thereof, eccentric loads for causing vibration of saidbase means and said seat.
 5. An apparatus for vibrating a seat asrecited in claim 4, wherein said eccentric loads comprise at least afixed load and at least an adjustable load.